A lab sample can be tested correctly and still leave a laboratory with a quality problem if its history is unclear.
Where was it collected? When was it received? Was it stored under the right conditions? Who handled it before testing? And can the final result be confidently traced back to the original sample?
These questions matter because laboratory quality is not determined by the analyzer alone. The U.S. CDC reports that about 14 billion laboratory tests are performed annually in the United States, with laboratory results influencing around 70% of medical decisions. When testing happens at that scale, consistent sample documentation and traceability become essential.
The risk becomes even clearer before analysis begins. A 2025 study published in Clinical Chemistry and Laboratory Medicine examined more than 11 million specimens and found that 98.4% of the documented errors occurred in the pre-analytical phase, with specimen hemolysis accounting for 69.6% of all recorded errors.
For quality managers, this makes sample documentation more than a record-keeping exercise. It provides the evidence needed to trace a sample’s journey from collection and receipt through handling, testing, storage, reporting, and final disposal.
What Is Laboratory Sample Documentation?
Laboratory sample documentation is the information recorded throughout a sample’s lifecycle. It can include where the sample came from, when it was collected, how it was received, how it was handled and stored, which tests were performed, and what happened to it afterward.
It is useful to distinguish between documents and records. Documents provide instructions, such as SOPs, policies, and work instructions. Records provide evidence that an activity was performed or a result was generated, such as sample logs, test records, raw data, and reports.
This distinction is important because quality management depends on both. WHO’s laboratory quality management guidance identifies documentation and reliable processes as fundamental to maintaining accurate, timely, and dependable laboratory results.
For laboratories working to ISO/IEC 17025 requirements, sample handling and sampling are also part of the standard’s scope. ISO describes ISO/IEC 17025 as a standard for laboratories performing testing, sampling, or calibration that want to demonstrate their competence and generate valid results.
For sample management, the goal is straightforward: create records that allow each sample and its associated data to be traced throughout its lifecycle.
Which Records Should Be Kept for Laboratory Samples?
The exact records required depend on the laboratory, sample type, applicable regulations, and quality system. However, a complete laboratory sample record commonly includes the following.
1. Sample Identification Records
Every sample should have a unique identifier that distinguishes it from other samples.
Identification records may include:
- Unique sample ID
- Sample type
- Batch or lot number
- Source or origin
- Client or project information
- Collection date and time
- Collector or submitting organization
- Required test or analysis
WHO laboratory quality standards for sample identification recommend assigning primary samples a unique identification or accession number and recording relevant receipt information.
The same identifier should remain associated with the physical sample and its records throughout the workflow.
2. Sample Receipt Records
The laboratory should document what happens when a sample arrives.
Receipt records can include:
- Date and time received
- Person receiving the sample
- Sample condition
- Packaging condition
- Temperature, where applicable
- Quantity or volume
- Label verification
- Requested analysis
- Acceptance or rejection status
- Reason for rejection, if applicable
Recording this information at receipt establishes an initial reference point and helps identify problems before testing begins.
3. Sample Handling and Preparation Records
Any activity that changes or prepares a sample should be documented where relevant.
This may include:
- Sample preparation
- Sub-sampling
- Dilution or extraction
- Transfers between containers
- Preparation conditions
- Reagents or materials used
- Personnel performing the activity
- Date and time of the activity
These records connect the original sample to the material that was ultimately tested.
4. Sample Storage Records
Sample records should make it possible to determine where a sample is stored and under what conditions.
Depending on the laboratory, this may include:
- Storage facility
- Refrigerator, freezer, cabinet, or other unit
- Shelf, rack, box, or position
- Storage temperature
- Date placed into storage
- Date removed from storage
- Person responsible for the movement
Laboratories should define clear requirements for sample retention, storage conditions, and disposal as part of their sample management procedures.
5. Testing and Result Records
Test results should remain clearly connected to the sample from which they were generated.
Records may include:
- Test method
- Instrument or equipment used
- Analyst
- Date and time of testing
- Raw data
- Calculations
- Observations
- Results
- Quality control information
- Deviations or nonconformities
- Final report
The connection between the sample, testing activity, raw data, and final result is essential for traceability and later review.
6. Sample Transfer and Chain-of-Custody Records
Whenever a sample moves between people, locations, departments, or facilities, the movement should be traceable.
A transfer record may include:
- Sample ID
- Date and time
- Previous location
- New location
- Person releasing the sample
- Person receiving the sample
- Reason for transfer
This creates a chain of custody and establishes who handled the sample at each stage.
7. Retention and Disposal Records
Sample documentation should not end when testing is complete.
Laboratories should define how long samples and associated records need to be retained and what happens when the retention period ends. Samples may be archived, returned, transferred, or disposed of depending on applicable requirements.
A disposal or archival record can include:
- Sample ID
- Disposal or archival date
- Person responsible
- Method or destination
- Reason for disposal
The 8 Best Practices for Laboratory Sample Record-Keeping
Having a list of required records is only the starting point. Laboratories also need consistent practices for creating, maintaining, and retrieving those records.
1. Assign a Unique Sample ID
Use a consistent identification system from the moment a sample enters the laboratory.
The same identifier should connect the physical sample with its documentation, storage location, testing records, and final results. This creates a reliable link between the sample and its associated information.
2. Record Information at the Time of the Activity
Sample records should be created as activities happen rather than reconstructed later.
Recording information when the activity occurs reduces the risk of forgotten details, inaccurate timestamps, or missing information. It also creates a clearer history when records are reviewed during an audit or investigation.
3. Standardize Sample Labels and Records
Different teams should not use different formats for the same information.
Standardized fields for sample IDs, dates, storage locations, test information, and status make records easier to understand and retrieve. Where appropriate, barcodes or other machine-readable identifiers can also reduce manual data entry.
4. Document Important Sample Movements
A sample should never appear to disappear between stages.
Whether it moves from receiving to storage, storage to preparation, preparation to testing, or one department to another, important movements should be recorded.
This becomes particularly important when samples are handled by multiple people or departments.
5. Keep Sample Records Secure and Retrievable
Good record-keeping is not just about storing information. Staff need to be able to find the correct record when they need it.
Laboratories should establish clear rules for where records are stored, who can access them, how they are protected, how long they are retained, and how changes are documented.
6. Link Results Directly to Sample Records
A test result has limited value if it cannot be confidently connected to the correct sample.
The sample ID should connect the original submission information with preparation records, testing data, quality control results, and the final report. This becomes particularly important when laboratories process many samples simultaneously.
7. Maintain an Audit Trail for Changes
Sample records may sometimes need corrections or amendments. Those changes should be controlled rather than simply replacing the original information.
A reliable record should make it possible to determine:
- What was changed
- When it was changed
- Who made the change
- Why the change was made, where required
This preserves the history of the record and supports investigations when discrepancies occur.
8. Define Retention and Disposal Rules
Laboratories should establish retention periods for relevant sample records and determine what happens when those periods end.
Retention requirements vary depending on the laboratory, industry, customer requirements, and applicable regulations. A defined retention schedule helps prevent records from being lost prematurely while avoiding uncontrolled accumulation of outdated information.
How to Maintain Sample Traceability From Collection to Disposal
Effective sample traceability means being able to follow a sample and its associated records throughout its lifecycle:
Collection → Receipt → Storage → Preparation → Testing → Reporting → Retention or Disposal
At every stage, the record should clearly show what happened, when it happened, and who was responsible. This creates a continuous history that quality checks, audits, or investigations can review.
For laboratories managing large numbers of samples, sample tracking can help connect identification, storage, movement, testing, and final disposition in a more traceable workflow.
Common Laboratory Sample Documentation Mistakes
Even when laboratories have established procedures, documentation gaps can occur when processes rely heavily on manual work or inconsistent practices.
Common issues include:
- Missing or incorrect sample identifiers
- Incomplete sample receipt information
- Inconsistent labeling
- Unrecorded sample transfers or storage locations
- Results that cannot be clearly linked to the original sample
- Records entered after an activity occurred
- Changes made without a clear audit trail
- Records scattered across disconnected spreadsheets and files
These gaps can make it harder to reconstruct what happened to a sample and increase the effort required during audits or investigations. Consistent procedures for sample handling can help reduce errors that affect sample integrity and traceability.
Frequently Asked Questions
What is the difference between a document and a record in a laboratory?
Documents provide instructions for how an activity should be performed, such as SOPs, policies, and work instructions. Records provide evidence that an activity was performed or that a result was generated, such as sample logs, raw data, and laboratory reports.
What is chain of custody in a laboratory?
Chain of custody is the documented trail showing who handled a sample, when it was handled, and where it moved throughout its lifecycle. It can cover the sample’s journey from collection and receipt through testing, storage, transfer, and final disposal.
How long should laboratory sample records be kept?
The required retention period depends on the laboratory, industry requirements, customer requirements, and applicable regulations. Laboratories should define a clear retention schedule and apply it consistently to samples and their associated records.
How a LIMS Improves Laboratory Sample Record-Keeping
Laboratories managing a growing number of samples may find manual documentation increasingly difficult to maintain consistently.
A digital sample management system can centralize sample information and connect different stages of the workflow. Depending on the system, this can include sample identification, storage locations, movements, testing information, results, and retention records.
Digital workflows can also reduce repetitive data entry and make information easier to search and retrieve.
A LIMS can connect sample IDs with test data and create a more continuous record of the sample lifecycle. This can support sample traceability and improve visibility into sample-related information.
The goal is not simply to replace paper records with digital ones. A useful system should make the workflow itself more traceable, searchable, and consistent.
Laboratory Sample Documentation Checklist
Use this checklist to quickly review whether a sample record contains the information needed for traceability:
| ✓ | What to document | Why it matters |
| ☐ | Sample ID | Uniquely identifies the sample throughout its lifecycle |
| ☐ | Source and collection details | Shows where, when, and from whom the sample was collected |
| ☐ | Receipt information | Records when the sample arrived and its condition |
| ☐ | Storage details | Shows where the sample is stored and under what conditions |
| ☐ | Handling and preparation | Documents activities that may affect sample integrity |
| ☐ | Transfers and movements | Maintains traceability when the sample changes location or custody |
| ☐ | Testing and results | Connects the sample to the work performed and its results |
| ☐ | Changes or amendments | Preserves the history of corrections or updates |
| ☐ | Retention period | Establishes how long the sample and records should be kept |
| ☐ | Disposal or archival | Documents what happened when the retention period ended |
The exact requirements should be adapted to the laboratory’s activities, sample types, quality system, and applicable regulatory or organizational requirements.
Simplify Sample Documentation with QISS LAB
Strong documentation and record-keeping give laboratories a clear history of every sample and the activities associated with it. From collection and receipt to testing, storage, and final disposal, each stage should contribute to a consistent and retrievable record.
For laboratories still relying on disconnected spreadsheets, paper forms, or manual sample logs, sample management software can centralize sample information, improve visibility, and support traceability throughout the sample lifecycle.
QISS LAB brings these workflows together in a laboratory information management system designed to help laboratories manage samples, information, and related workflows more systematically.
If your laboratory wants to improve sample traceability and reduce the effort involved in maintaining sample records, request a free demo to see how QISS LAB can support your workflow.
